In astronomy one method of classifying stars is through the analysis of their absorption spectra, by this method stars are assigned a spectral class. Since the absorption spectra is dependent on the surface temperature of the star the spectral class gives an indications of the temperature of the star. Radio telescopes are among many different tools used by astronomers Astronomy (Greek: αστÏονομία = άστÏον + νόμος, astronomia = astron + nomos, literally, law of the stars) is the science of celestial objects and phenomena that originate outside the Earths atmosphere, such as stars, planets, comets, auroras, galaxies, and the cosmic background radiation. ... Electromagnetic radiation may be characterised by its wavelength. ... Electromagnetic radiation may be characterised by its wavelength. ...
The current system of naming spectral class was adopted in 1910 and consists of a letter and a number from 0 to 9, for example the spectral class of the sun is G2. The letters used are in decreasing order of temperature
O B A F G K M
The number is used to sub-divide these with the lower the number the higher the temperature so a star classed as F4 would be hotter than a star classed as F9.
In astronomy one method of classifying stars is through the analysis of their absorption spectra, by this method stars are assigned a spectralclass.
Since the absorption spectra is dependent on the surface temperature of the star the spectralclass gives an indications of the temperature of the star.
The current system of naming spectralclass was adopted in 1910 and consists of a letter and a number from 0 to 9, for example the spectralclass of the sun is G2.
Class O stars are very hot and very luminous, being bluish in colour; in fact, most of their output is in the ultraviolet range.
Class W is subdivided into subclasses WN and WC according to the dominance of nitrogen or carbon in their spectra (and outer layers).
Class R and N stars are carbon stars (red giants thought to reach the end of their life) which run parallel to the normal classification system from roughly mid G to late M. These have more recently been remapped into a unified carbon classifier C, with N0 starting at roughly C6.
Feeds |
Contact